product review
Nexus Greenhouse
Greenhouse Systems:
Systems:
Nexus
The XY System
Everything you wanted to know about this new technology
and how it could change greenhouse production.
By Bridget White
O
K, so what is XY? It
doesn’t sound like
any sort of automation U.S. growers
have ever used. Our automation has
very pragmatic names like transplanters or flat fillers or conveyers.
In short, XY refers to the coordinates on a grid system (think
back to high school math). This
automated system allows a grower to know where every plant, flat
or bench is located on this grid
and to quickly access product
using grid-based automation. This
is very important to growers who
produce a large number of varieties and are dependent on a very
compressed shipping season.
In any U.S. production facility,
product is moved from the growing
area to the shipping area to the customer in large quantities, sometimes
consisting of hundreds of varieties.
In an XY-equipped greenhouse,
when a plant is selected to be
shipped, a robot or overhead crane
will “find” the carrier by consulting
the computerized location system
and bring it to the shipping area.
This system is fast, safe and labor
efficient and holds great promise for
the U.S. market, and Nexus
Greenhouse Systems has just introduced it to the U.S. market.
I actually saw the first xy components being manufactured a year ago
in The Netherlands during Hortifair
and found it to be fascinating in the
opportunities it affords growers. In
fact, Visser, manufacturer of the XY
system, technicians transported the
actual system I’ll be discussing
below into a neighboring field to
show us how it operated and to test
it one final time before delivery.
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SYSTEM BASICS
This system for the transportation and growing of plant product
consists of three basic elements: Xtransporter, Y-transporter and a
loading/unloading system.
The core of the XY system is a
pick and place unit that removes
growing material from greenhouse
bays (the Y direction). The unit is driven by an operator and can selectively pick product from anywhere in
each bay. It rides on steel rails into
the bays, eliminating the need for a
concrete floor. During peak shipping
periods, the pick and place unit can
comfortably clear two acres of greenhouse in a single day. Small overhead cranes can also be used (in a
totally automated option) in both
new and existing operations, as most
greenhouses have enough gutter
height to accommodate a crane.
The second part is the mecha-
nism to move material to and from
the greenhouse, headhouse and
shipping area (the X direction). The
transport robot rides on a concrete
transport aisle and is electrically
powered with no operator.
A compare and contrast of the different functions of these two items
might facilitate understanding.
• The Y-transporter only moves
into and out of the bays of the
greenhouse; the X-transporter runs
on the center path between bays
and the headhouse.
• The Y-transporter picks up
the plant carriers, as an example,
in the greenhouse and drives
onto the X-transporter, which is
waiting on the center path for
the carriers. The X-transporter
takes the carriers to the loading
station while the Y-transporter
picks up a new load of carriers.
• When the Y-Transporter needs
to go to another bay, it moves onto
the X-transporter and together they
drive to the required bay, after
which the Y-transporter drives into
the bay to pick up a load of carriers.
And the process starts all over again.
The third part of the system is the
carrier (whatever holds the flats,
packs or pots). The XY incorporates
carriers specially designed with
racks the same size as cart shelves,
which can stack on a traditional cart
base and serve double duty as shipping carts. Less expensive carriers
can be designed that do not have
the dual function.
THE FIRST
INSTALLATION
Top: Planted trays on carriers; Middle: The Y axis pick and place unit transfers racks of carriers
from the floor of the greenhouse to the center aisle; Bottom: The X axis transport car travels up
and down the center aisle to transfer racks from the greenhouse to the shipping or planting area.
September 2003
Unlike many pieces of automation, the Nexus-Visser XY system has
been manufactured with the U.S. ➧
product review
grower specifically in mind. It has
the flexibility to accommodate the
large numbers of varieties and pot
sizes common in U.S. greenhouses,
and growing containers can easily be
converted into that all important
grower headache: transport carts.
It might sound odd to say that
the first installation of a piece of
automated equipment specifically
designed for the U.S. market took
place in England — Chichester,
England to be exact — but it did.
Roundstone Nurseries, a wholesale
grower located in the South of
England and a producer of 26 different species and hundreds of cultivars, has worked in close cooperation with Visser for almost 20 years
and, as a close-to-home version of
U.S. production, Visser thought the
Roundstone facility was a logical
first installation.
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Carriers can be stacked on top of one another and placed on a cart base for shipping.
Starting from a green field or a
completely new site, as Fred
Milbourne, owner of Roundstone
Nurseries says, made their application a simple matter of design-
September 2003
ing the site and installing the
equipment. Milbourne considered
other systems, such as a container
bench system, but ultimately
decided on the XY because they
“felt [it] would suit our requirements better. It’s more flexible,
gives better access to the crop, better utilization of space and is
faster,” explained Milbourne.
The Roundstone installation
was completed in January 2004,
just in time for full spring production using the new system. “We
worked with it 24 hours a day,
seven days a week,” boasted
Milbourne, “so the learning curve
was very steep. We are very fortunate to have good people in operations and engineering, so we managed, I think, very well.”
“First of all,” continued
Milbourne, “the installation went
very well. Visser came in on time
and finished on time. From that
point there were absolutely no
problems. To say that we had no
problems once we started running
product review
the system at capacity would not
be true, but I think you have to ask
yourself with an installation of this
size, what is an acceptable level of
problems? We had some component failures within the equipment
that were quite easily fixed by our
own engineering team and supported by Visser ’s, and we had
some software problems. However,
none of these problems interfered
or brought production to a standstill, which I believe is the most
important thing, and I think this is
almost inevitable with an installation of this size.”
$3.50 per square foot. In a situation
such as Roundstone’s, it’s hard to
determine exact equipment cost or
even payback, as all costs are bun-
quick 3-4 years, but there are many
design options available, with
costs varying accordingly.
As Mike Porter, president of
GOOD TO KNOW
An XY system is not the cheapest piece of automation you can go
with, and it’s not for the faint of
heart. This is serious automation
for growers who move a serious
amount of product, and the cost is
in line with the level of sophistication. The estimated cost for the
components described above, plus
the dual-use carriers, is less than
The transfer shuttle, stationed in the headhouse near shipping, removes the racks of carriers
from the transport car and stacks them up.
dled together, but the anticipated
payback for the entire project,
including the automation, is a
Nexus, said, “Each system is
unique in some way as it provides
a match between available
automation equipment and the
grower’s individual needs.” The
amount of planning that is put
into the design of the XY system
has a “resulting increase in efficiency, quality and profitability
that’s hard to measure.”
The XY System will make a significant change in how many customers will do business. It is a system that makes sense and has been
thought out very well. Working
with the Nexus team, a grower can
design a new project or redesign an
existing one that incorporates all or
parts of the total XY.
The XY system is manufactured by Visser International
Trade and Engineering, the largest
supplier of machines and systems
for the horticultural industry, and
distributed in the United States
exclusively by Nexus. GPN
Bridget White is editorial director of
GPN. She can be reached by phone
at (847) 391-1004 or E-mail at
[email protected].
September 2003
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